#include<stdio.h>
#define NUM 8
int a[NUM+1];
int main()
{
    int i,k,flag,not_finish=1,count=0;
    i=1; 
    a[1]=1;
    printf("The possible configuration of 8 queens are:\n");
    while(not_finish)
    {
        while(not_finish&&i<=NUM) 
        {
            for(flag=1,k=1;flag&&k<i;k++) 
                if(a[k]==a[i])flag=0;
            for(k=1;flag&&k<i;k++)
                if((a[i]==a[k]-(k-i))||(a[i]==a[k]+(k-i))) flag=0;
                if(!flag)
                {
                    if(a[i]==a[i-1]) 
                    {
                        i--; 
                        if(i>1&&a[i]==NUM)
                            a[i]=1; 
                        else if(i==1&&a[i]==NUM)
                            not_finish=0; 
                        else a[i]++; 
                    }
                        else if(a[i]==NUM) a[i]=1;
                        else a[i]++; 
                }
            else if(++i<=NUM)
            if(a[i-1]==NUM) a[i]=1; 
            else a[i]=a[i-1]+1; 
        }
        if(not_finish)
        {
            ++count;
            printf((count-1)%3?" [%2d]: ":" \n[%2d]: ",count);
            for(k=1;k<=NUM;k++)
                printf(" %d",a[k]);
            if(a[NUM-1]<NUM) a[NUM-1]++; 
            else a[NUM-1]=1;
            i=NUM-1; 
        }
    }
}